Shopping-cart coupling locks are opened by a pledge in the form of a coin or token, so that one cart can be uncoupled from another. The coin or token remains held in the lock until the cart is again coupled to another cart or location. Frequently the shopper does not always have a coin handy, and the search for a coin before he or she can use a shopping cart leads to annoyance.
As described in my copending applications Ser. Nos. 08/254,293 and 08/258,977 respectively filed 6 Jun. 1994 and 10 Jun. 1994 as well as in my numerous earlier patents and patent applications cited therein, such a lock (as specifically detailed in my U.S. Pat. No. 5,377,806 issued 3 Jan. 1995 has a housing formed with an outwardly open latch port and an actuating port, a latch member adapted to be inserted into the latch port, an actuator--normally either a card, token, or coin--adapted to be inserted into the actuating port, and a latch element movable between a holding position retaining the latch member against removal from the latch port and a freeing position permitting such removal. A control element is movable on insertion of the actuator into the actuating port from a locked to an unlocked position, and interengageable formations on the elements displace the latch element into the freeing position on displacement of the control element by the actuator into the unlocked position.
Thus with this system the token, coin, or card used as actuator directly engages the control element and directly actuates the lock to release the latch member. Thus the user need merely poke his coin, token, or card into the actuating port to free the latch member and make use of the cart carrying the lock.
Even such a system can be a problem for someone who is not carrying the requisite coin, token, or card. What is more such a system does nothing to encourage customer loyalty by giving regular customers an advantage.